ather(o)-

An atheroma.

Greek athērōma, from athērē, atharē, porridge or groats.

Atheroma is a medical condition of the walls of the arteries caused by accumulated fatty deposits and scar tissue; it is so called because the fatty deposits are of a porridge-like consistency. The resulting disease is atherosclerosis, and the adjective is atheromatous; the surgical removal of an atheroma is atherectomy (Greek ektomē, excision).